1. Field of the Invention
The present invention relates to an IC (i.e., integrated circuit) tag and label having an IC encapsulated therein which comprises a wiring circuit and an IC circuit for the transmission and reception of data incorporated in its laminated structure and thus can write and read data.
The IC tag and label obtained according to the invention allow data to be recorded on the surface thereof. The IC tag and label of the invention are free from security problem that the inner circuit or wiring circuit can be seen through. The IC tag and label of the invention are excellent in strength and water resistance and thus can be used even in the atmosphere and water, indoor or outdoor. Accordingly, the IC tag and label of the invention can be used for frozen food vessels, industrial products, various chemical vessels, etc. and for flow control, production line control, etc.
2. Discussion of the Background
In recent years, a card comprising an IC module encapsulated therein which performs non-contact transmission/reception of data via external reader and writer has spread. An IC tag or label having an adhesive layer which is applied to the adherend for use has been proposed for the same purpose. For example, Japanese Patent Laid-Open No. 1999-277961, Japanese Patent Laid-Open No. 1999-277963, Japanese Patent Laid-Open No. 1999-134460 and Japanese Patent Laid-Open No. 1999-231782 disclose the structure and usage of IC tag and label.
It is therefore an object of the invention to provide an IC tag or label which realizes data recording properties, security, strength and water resistance such that the purpose of IC tag or label disclosed in the above cited patents can be further expanded.
The foregoing object of the present invention will become apparent from the following detailed description and examples.
In accordance with the present invention, a specific laminated structure is defined and the properties of the surface thermoplastic resin film to be used is defined. Accordingly, the IC tag or label of the invention can be externally viewed as a mere conventional paper adhesive label or paper tag without any sense of incompatibility though having an IC circuit layer comprising an IC circuit and a wiring circuit incorporated therein or thereon and excellent strength and water resistance.
The present invention provides an IC tag having a laminated structure comprising a thermoplastic resin film layer (A), an adhesive layer (D), and an IC circuit layer (B) or an IC circuit protective layer (C) having a hole containing an IC circuit layer (B); an IC label having a laminated structure comprising a thermoplastic resin film layer (A), an adhesive layer (D), an IC circuit layer (B) or an IC circuit protective layer (C) having a hole containing an IC circuit layer (B), and an adhesive layer (G); and an airline tag comprising the IC label.
In a preferred embodiment of the IC tag and label according to the invention, a light shielding layer (E) is preferably provided interposed between the thermoplastic resin film layer (A) and the IC circuit layer (B). Further, a thermoplastic resin film layer (F) and an adhesive layer (D) are preferably provided interposed between the light shielding layer (E) and the IC circuit layer (B).
The IC circuit layer (B) has a smaller size than the IC tag and label and a thickness less than or equal to the thickness of the IC circuit protective layer (C). An adhesive layer (D) is preferably provided interposed between the thermoplastic resin film layer (A) and the IC circuit protective layer (C). A light shielding layer (E) is preferably provided interposed between the thermoplastic resin film layer (A) and the IC circuit protective layer (C). Further, and adhesive layer (D) and a thermoplastic resin film layer (F) having a light shielding layer (E) provided on at least one surface thereof are preferably provided interposed between the thermoplastic resin film layer (A) and the adhesive layer (D).
The IC tag and label preferably exhibit a whiteness degree of not smaller than 85% and a total light transmittance of nut greater than 15%.
The thermoplastic resin film layer (A) preferably exhibits an opacity of not smaller than 80% and a whiteness degree of not smaller than 90%.
The thermoplastic resin film layer (A) preferably exhibits a porosity of from 10% to 60% as calculated by the following equation:
% Porosity={(xcfx810xe2x88x92xcfx81)/xcfx810}xc3x97100xe2x80x83xe2x80x83(1) 
where xcfx810 represents the true density of the film; and xcfx81 represents the density of the film.
The thermoplastic resin to be used in the thermoplastic resin film layer (A) and the thermoplastic resin film layer (F) is preferably a polyolefin resin and/or polyester resin, and the polyolefin resin is preferably a propylene resin. Further, the thermoplastic resin film layer (A) preferably has a recording layer provided on the surface thereof.